Datacentre Virtualisation: Top Five Mistakes

4.    Planning a multi-data centre solution without benefiting from a true GSLB solution
Server virtualisation makes it far easier for IT managers to design data centre disaster recovery, deploy applications within multiple data centres or to move applications between data centres. This is because there is no need to install a new physical server, but instead use the existing server infrastructure for more applications.

If applications are to be deployed in multiple data centres it is vital that each transaction is carried through to completion. To accomplish this, a user’s transaction must be directed to an available site that knows the user’s information and the status of the transaction.
Solution: By using an ADC to support global traffic redirection (GSLB), issues like business fluctuations (bursts and peaks) and potential application or network failures can be averted. Users are directed to the site that can deliver the best experience.

When choosing an ADC the IT manager must be sure it can guarantee both transaction completion and fast response times. This is done by optimising globally distributed server resources across multiple datacentres based on application/transaction persistency, content availability, load and proximity.
5.    Architecting a virtualised environment while overlooking the potential security risks

As discussed above, one of the main benefits of server virtualisation is that VMs share a common physical infrastructure.  However this is also a weakness because any issue affecting the physical infrastructure effects all hosted applications (VMs).  One such issue is DoS (Denial of Service) attacks which may target a physical server’s network card, preventing it from passing legitimate traffic to hosted applications, causing applications downtime.

Additionally, if the virtualised infrastructure supports auto scaling capabilities, a DoS attack targeting an application may cause it to continuously scale up to handle the “bogus” traffic, increasing the cost of operation without any business benefit.

Solution: To prevent such scenarios, IT managers should implement a real-time network attack prevention device, one that fully protects the virtualised infrastructure against known and emerging network security threats. It should also be able to detect and mitigate emerging network attacks in real time i.e. zero-minute attacks, DoS/DDoS attacks and application misuse attacks – all without the need for human intervention or blocking legitimate user traffic.

Conclusion
To summarise, when designing a virtual server architecture, IT managers need to ensure they do not over look availability, performance, alignment and security issues, all of which are derived from the virtualisation of applications and the use of a share physical environment.